Soil Fertilization with Palm Oil Mill Effluent Has a Short-Term Effect on the Bacterial Diversity of an Amazonian Agricultural Land Area.

Palm oil derived from the fruits of Elaeis guineensis Jacq. has global economic importance and is largely produced in tropical regions. The palm oil production process leads to a highly polluting waste called palm oil mill effluent (POME). A strategy commonly used by producers to overcome environmental issues and to improve soil fertility is the reuse of POME as a fertilizer due to the chemical and biological characteristics of the effluent. In this research, three groups were analyzed: soil without POME application (control group) and soil samples after 4 and 9 days of POME application. An environmental DNA metabarcoding approach was used. eDNA was extracted, and the V4 region of the 16S rRNA gene was amplified and sequenced in the Illumina MiSeq platform. The abundance of Proteobacteria (48.1%) and Firmicutes (9.0%) was higher in fertilized soil, while Bacteroidetes (20.3%) and Verrucomicrobia (7.8%) were more abundant in control soil. Additionally, the effluent seemed to modify soil characteristics favoring taxa responsible for the mineralization of organic compounds and nitrogen fixation such as species of Gammaproteobacteria class. Our study highlights the influence of POME on soil biological components and contributes to the sustainable production of palm oil in the Amazon.

Differential accumulation of proteins in oil palms affected by fatal yellowing disease.

There is still no consensus on the true origin of fatal yellowing, one of the most important diseases affecting oil palm (Elaeis guineensis Jacq.) plantations. This study involved two-dimensional liquid chromatography coupled with tandem mass spectrometry (2D-UPLC-MSE) analyses to identify changes in protein profiles of oil palms affected by FY disease. Oil palm roots were sampled from two growing areas. Differential accumulation of proteins was assessed by comparing plants with and without symptoms and between plants at different stages of FY development. Most of the proteins identified with differential accumulation were those related to stress response and energy metabolism. The latter proteins include the enzymes alcohol dehydrogenase and aldehyde dehydrogenase, related to alcohol fermentation, which were identified in plants with and without symptoms. The presence of these enzymes suggests an anaerobic condition before or during FY. Transketolase, isoflavone reductase, cinnamyl alcohol dehydrogenase, caffeic acid 3-O-methyltransferase, S-adenosylmethionine synthase, aldehyde dehydrogenase and ferritin, among others, were identified as potential marker proteins and could be used to guide selection of FY-tolerant oil palm genotypes or to understand the source of this anomaly. When comparing different stages of FY, we observed high accumulation of alcohol dehydrogenase and other abiotic stress related-proteins at all disease stages. On the other hand, biological stress-related proteins were more accumulated at later stages of the disease. These results suggest that changes in abiotic factors can trigger FY development, creating conditions for the establishment of opportunistic pathogens.

Hemaglutinina de folhas de mandioca (Manihot esculenta Crantz): purificação parcial e toxicidade / Hemaglutinin of cassava leaves (Manihot esculenta Crantz): partial purification and toxicity

Um dos componentes da multimistura para suplementação alimentar de populações carentes é a farinha de folhas de mandioca (FFM) que possui elevado conteúdo em proteínas, vitaminas e minerais. Todavia, as folhas de mandioca também apresentam substâncias antinutritivas e/ou tóxicas, como cianeto, polifenóis, nitrato, ácido oxálico, hemaglutinina, saponinas e inibidores de tripsina. Objetivou-se neste trabalho extrair as proteínas da FFM, purificando-as em coluna cromatográfica e determinar sua atividade hemaglutinante e toxicidade. Foram testadas várias estratégias de extração e precipitação das proteínas, sendo que o maior teor protéico e atividade hemaglutinante foi obtido na extração com água destilada na proporção 1:20 (p/v) seguida da precipitação com sulfato de amônio a 80 por cento de saturação. As proteínas precipitadas foram purificadas em coluna Q-Sepharose. Das quatro frações obtidas na purificação (I, II, III e IV), a I e a II apresentaram maiores atividades hemaglutinantes. As mesmas frações foram injetadas via intraperitoneal em camundongos com doses de 2mg (fração I), 3mg (fração II), 54mg (fração III) e 52mg (fração IV) para cada animal com 20g de peso médio, não sendo observadas mortes ou quaisquer efeitos adversos após 120h.

One of the components of the multimixture to the feed supplementation of low-income populations is cassava leaf flour (FFM), with high content of proteins, vitamins and minerals. However, cassava leaves also present substance regarded as antinutritive and/or toxic, such as cyanide, polyphenols, nitrate, oxalic acid, hemagglutinin, saponins and trypsin inhibitors. The aim of this work was to extract proteins from FFM, purifying them in chromatographic column and determine their hemagglutinating activity and toxicity. A number of strategies of extraction and precipitation of proteins were tested; the highest protein content and hemagglutinating activity were obtained in the extraction with distilled water at the 1:20 ratio (p/v) followed by the precipitation with ammonium sulfate at 80 percent of saturation. The precipitated proteins were purified in Q-Sepharose Fast Flow column. Out of the four purification fractions (I, II, III e IV), the I and II activities presented higher specific activity. The same fractions were injected intraperitoneal via in mice of 20g weight with doses of 2mg (fraction I), 3mg (fraction II), 54mg (fraction III) and 52mg (fraction IV). No deaths or any adverse effects was observed after 120h.

Alterações bioquímicas de plantas e morfológicas de gemas de cafeeiro associadas a eventos do florescimento em resposta a elementos meteorológicos / Biochemical alterations of plants and bud morphology of coffee tree associated to events on flowering in response to meteorological elements

O florescimento do cafeeiro envolve diversos fatores, tanto da planta como do ambiente. A compreensão das interações entre esses fatores pode contribuir para o desenvolvimento de práticas de manejo mais dequadas, principalmente em relação à irrigação. Tais práticas podem vir a promover uma uniformização da floração, conseqüentemente uniformização da maturação dos frutos, minimizando os custos de produção. O objetivo deste trabalho foi avaliar alterações morfológicas de gemas, síntese de prolina e de ácido abscísico em plantas de cafeeiros em resposta a elementos meteorológicos, visando assim contribuir para o conhecimento de fatores que influenciam a uniformização da floração. Foram feitas análises, por meio de técnicas de microscopia eletrônica de varredura, em gemas de ramos plagiotrópicos de primeira ordem, coletadas semanalmente durante o período de novembro/04 a fevereiro/05. No período de julho a setembro de 2005, foram realizadas avaliações em plantas irrigadas e não-irrigadas, de potencial hídrico foliar antes do amanhecer e teor de prolina, em folhas totalmente expandidas, posicionadas em ramos do terço superior da copa. Foi também avaliado o teor de ácido abscísico na seiva do xilema e nas gemas florais. Os resultados mostram modificações na estrutura das gemas associadas a um período de déficit hídrico seguido de precipitação e, conseqüentemente, de menor amplitude térmica. Em relação ao potencial hídrico, há diferenças entre os tratamentos irrigado e não-irrigado e foram observados valores entre -0,3 e -0,8MPa e -0,6 e -1,5MPa respectivamente. Os maiores valores de teores de prolina e de ABA correspondem a períodos de menor oferta de precipitação, entretanto, não há uma relação direta entre a síntese destes compostos e as fases do florescimento avaliadas.

Flowering on coffee plants involves several aspects from the plant as well as from the environment. Understanding these interactions can enhance the knowledge and promote better handling of the crop in field, mainly related to irrigation to promote synchronized flowering and consequently the uniform fruit maturation, lowering the production costs. The aim of the present study was to evaluate bud morphology, proline and abscisic acic biosynthesis on coffee plants under different environmental conditions in order to contribute to the knowledge in factors that influence flowering synchronization. Scanning electron microscopic was performed on buds of plagiotropic shoots weekly collected from November/04 to February/05. Predawn water potential and proline content analysis were carried out from July to September/05 using complete superior third expanded leaves from plagiotropic shoots of non and irrigated plants. Abcisic acid content was also evaluated in xylem sap and on flower buds. The results show alterations on bud morphology associated to the period of water deficit followed by precipitation and also, consequently, lower thermic amplitude. Regarding to the water potential, differences could be observed in the treatments having -0.3 and 0.8MPa for irrigated and -0.6 and -1.5MPa for non-irrigated plants. The highest proline and abcisic acid content are related to dryer period, however there is no direct relationship between these biosynthesis compounds and the different flowering stages evaluated.

Aspectos histoquímicos e morfológicos de grãos de café de diferentes qualidades / Histological and morphological aspects of different grain coffee qualities

Este trabalho teve por objetivo relacionar aspectos histoquímicos e morfológicos de grãos secos de café com a qualidade destes classificadas como bebida mole, dura e rio. Paralelamente a esses estudos, foram realizadas em cada lote de grãos a lixiviação de potássio, a condutividade elétrica e a atividade da polifenol oxidase. Uma maior lixiviação de potássio, com o conseqüente aumento na condutividade elétrica, mostrou ser um forte indicador de danos na membrana e parede celular. Este dano foi confirmado por fotomicrografias em estudos histoquímicos e morfológicos de grãos de café. Estes estudos mostraram que no café bebida mole havia corpos lipídicos globulares bem definidos no interior dos protoplastos. Com a perda da qualidade da bebida para dura e rio, verificou-se que os lipídeos não mais se apresentaram em corpos lipídicos bem definidos, estavam localizados nas regiões periféricas do protoplasto e algumas vezes extravasados no tecido devido à degradação da parede celular.

This research studied the histological and morphological aspects of the dry grain coffee classified as 'mole, 'dura' and 'rio' beverage. Concomitantly to these studies there were realized in each group of grains, potassium lixiviation, electric conductivity and polyphenol oxidase activity. A higher potassium lixiviation with the consequent increase in electric conductivity showed to be a strong indicator of membrane and cell wall damage. This damage was confirmed by histological and morphological studies of coffee grains. These studies showed that coffee beverage 'mole' had well defined lipidic bodies in the interior of protoplasts. During the beverage quality loss to 'dura' and 'rio', it was observed that lipids did not appear in well defined lipidic bodies like 'mole' coffee beverage, were localized in periphery of the protoplasts and sometimes extravased into the tissue due the degradation in cell wall.

Adubação do cafeeiro com nitrato de potássio via solo e folha, no outono-inverno e primavera-verão: efeitos na atividade da redutase do nitrato, no crescimento das plantas e na produção / Coffee tree fertilization with potassium nitrate via leaf and soil, in autumn-winter and spring-summer: effects on nitrate reductase activity, on plant growth and production

Objetivou-se verificar o efeito da adubação de 100 g de N/ano/planta, em três épocas (outono-inverno, primavera-verão e outono-inverno/primavera-verão) e três modos de aplicação (folha, solo e folha/solo), no desenvolvimento, na produção e na atividade da redutase do nitrato (RN) da cultivar Rubi-MG com quatro anos de idade. A análise conjunta entre o modo e época de aplicação mostra que o padrão de RN não se altera, sendo no frio maior nas raízes e no calor maior nas folhas. O mesmo aconteceu com o padrão de crescimento, rápido na estação quente/chuvosa e lento no período seco/frio. Em função da época de adubação, concluiu-se que, no outono-inverno, deve-se dar preferência pela aplicação na folha ou folha-solo. Esses modos de adubação foram os mais eficientes na retomada do crescimento. Quando as adubações ocorrerem nos dois períodos, qualquer um dos três modos pode ser utilizado. Apesar da inviabilidade de várias pulverizações, eventualmente, uma ou mais pulverizações com KNO3 podem substituir eficientemente a adubação no solo.

The objective of this work was to verify the effect of the fertilization of 100g N/year/plant, in three periods (autumn-winter, spring-summer and autumn-winter/spring-summer) and three types of application (leaf, soil and leaf/soil) on the development, production and nitrate reductase activity (NR) on four years old Rubi-MG cultivar. The analysis of type and time of application showed no alteration on NR activity being higher on roots in cold weather and higher on leaves in warmer weather. The same was observed with growth pattern, fast in hot/rain season and slow in dry/cold period. During autumn-winter, applications may be performed on leaf or leaf-soil. These types of fertilization were the most efficient during growth recovering. When the fertilization occurred in both periods, any type may be used. Although, several pulverizations are nonviable, one or more pulverization with KNO3 can efficiently replace soil fertilization.